The present invention relates to a process for producing a throttle-valve and its housing. The two may be used in a motor vehicle and comprise injection moldings. The throttle-valve housing has a through-flow orifice which can be blocked off by the throttle valve. The valve includes a pivot axis which extends transversely to the longitudinal axis of the passage orifice and along which the throttle valve has a continuous shaft bore. The throttle-valve shaft can be inserted into the bore in a rotationally fixed manner. The ends of the shaft project out of the bore on opposing sides and into bearing bores in the housing. The bearing bores are coaxial with respect to the shaft bore. The throttle valve, in its closed position, bears against the inner wall of the through-flow orifice by means of its radially encircling edge.
For throttle-valve housings, it is particularly important for the through-flow orifice to be blocked off as completely as possible when the throttle valve is in its closed position. This is particularly necessary if the throttle-valve housing is arranged in the air supply line of an internal combustion engine.
Throttle-valve housings are often produced by injection molding. Due to manufacturing tolerances, the through-flow orifice cannot be substantially completely blocked off. To eliminate this drawback, it is known for a plastic throttle valve to be injection-molded separately into a throttle-valve housing which has already been fully produced. Accordingly, the throttle valve is matched to the throttle-valve housing.
This process is highly complex, in particular, on account of the two injection-molding processes.